This invention relates to novel thiophene or furan herbicides and their use as agricultural chemicals. In particular, they are useful as pre- and postemergence herbicides and as plant growth regulants. Certain compounds within the scope of the instant invention have shown crop selectivity and in particular have shown selectivity toward corn.
Levitt U.S. Pat. No. 4,169,719 discloses herbicidal thiophene and furan sulfonylureas such as: ##STR1## wherein R.sub.8 is H, Cl, Br or CH.sub.3 ;
R.sub.9 is H, Cl, Br or CH.sub.3 ; PA1 R.sub.10 is H, Cl, Br or CH.sub.3 ; PA1 R.sub.1 and R.sub.2 are independently C.sub.1 -C.sub.3 alkyl. PA1 A is ##STR5## and; B is ##STR6## R.sub.4 is H or CH.sub.3 ; R.sub.5 is H, CH.sub.3 or OCH.sub.3 ; and PA1 R.sub.1 is ##STR7## PA1 A is ##STR10## R.sub.1 is R.sub.6 S[O].sub.n ; R.sub.6 is C.sub.1 -C.sub.4 alkyl, C.sub.3 -C.sub.4 alkenyl, cyclopentyl or cyclopropylmethyl; PA1 R.sub.2 is H, Cl, Br or CH.sub.3 ; PA1 R.sub.3 and R.sub.4 are independently H or CH.sub.3 ; n is 0, 1 or 2; and PA1 Y is H, Cl, CH.sub.3, C.sub.2 H.sub.5, OCH.sub.3, OC.sub.2 H.sub.5 or CH.sub.2 OCH.sub.3 ; PA1 Y.sub.1 is H, Cl, CH.sub.3 or OCH.sub.3 ; PA1 Y.sub.2 is CH.sub.3 or OCH.sub.3 ; PA1 Z is CH or N; PA1 (1) Compounds of Formula I where Q is S; PA1 (2) Compound of Preferred (1) where R.sub.2 is H; PA1 (3) Compounds of Preferred (2) where R.sub.6 is C.sub.1 -C.sub.3 alkyl; PA1 (4) Compounds of Preferred (3) where n is 2; PA1 (5) Compounds of Preferred (4) where ##STR12## (6) Compounds of Preferred (5) where R.sub.3 is H; (7) Compounds of Preferred (6) with the structure ##STR13## (8) Compounds of Preferred (6) with the structure ##STR14## (9) Compounds of Preferred (6) with the structure ##STR15## (10) Compounds of Preferred (7) where X is CH.sub.3 or OCH.sub.3 ; and Y is CH.sub.3, OCH.sub.3, OC.sub.2 H.sub.5 or CH.sub.2 OCH.sub.3 ; PA1 (11) Compounds of Preferred (8) where X is CH.sub.3 or OCH.sub.3 ; and Y is CH.sub.3, OCH.sub.3, OC.sub.2 H.sub.5 or CH.sub.2 OCH.sub.3 ; PA1 (12) Compounds of Preferred (9) where X is CH.sub.3 or OCH.sub.3 ; and Y is CH.sub.3, OCH.sub.3, OC.sub.2 H.sub.5 or CH.sub.2 OCH.sub.3 ; PA1 (13) Compounds of Preferred (10) where R.sub.4 is H; PA1 (14) Compounds of Preferred (11) where R.sub.4 is H; PA1 (15) Compounds of Preferred (12) where R.sub.4 is H; PA1 (16) Compounds of Formula I where Q is O; PA1 (17) Compounds of Preferred (16) where R.sub.2 is H; PA1 (18) Compounds of Preferred (17) where R.sub.6 is C.sub.1 -C.sub.3 alkyl; PA1 (19) Compounds of Preferred (18) where n is 2; PA1 (20) Compounds of Preferred (19) where ##STR16## (21) Compounds of Preferred (20) where R.sub.3 is H; (22) Compounds of Preferred (21) with the structure ##STR17## (23) Compounds of Preferred (21) with the structure ##STR18## (24) Compounds of Preferred (21) with the structure ##STR19## PA1 R.sub.1 is R.sub.6 S[O].sub.n ; PA1 R.sub.6 is C.sub.1 -C.sub.4 alkyl, C.sub.3 -C.sub.4 alkenyl, cyclopentyl or cyclopropylmethyl; and PA1 n is 0 or 2; PA1 R.sub.1 and the sulfonylisocyanate group are bonded to adjacent carbon atoms of the furan or thiophene ring. PA1 (1) Compounds of Formula II with the structure ##STR21## (2) Compounds of Formula II with the structure ##STR22## (3) Compounds of Formula II with the structure ##STR23## and (4) Compounds of Preferred (2) wherein R.sub.1 is R.sub.6 SO.sub.2, and R.sub.6 is C.sub.1 -C.sub.3 alkyl. PA1 R.sub.6 is C.sub.1 -C.sub.4 alkyl, C.sub.3 -C.sub.4 alkenyl, cyclopentyl or cyclopropylmethyl; PA1 n is 0 or 2; and PA1 Z is CH or N. PA1 R.sub.1 and the sulfonylureido group are bonded to adjacent carbon atoms of the furan or thiophene ring. PA1 R.sub.9 =Cl, Br; and PA1 R.sub.2 =H, CH.sub.3, Cl and 4--Br. PA1 R.sub.11 =Cl, Br or CH.sub.3, provided that R.sub.10 and R.sub.11 cannot both be CH.sub.3 ; PA1 R.sub.2 =H, Cl, Br or CH.sub.3 ; and PA1 R.sub.6 and R.sub.8 are as previously defined. PA1 M=Na, K or Cu; and PA1 R.sub.2 and R.sub.6 are as previously defined. PA1 R.sub.2 and R.sub.6 are as previously defined. PA1 R.sub.6 and R.sub.8 are as previously defined. PA1 R.sub.2 is CH.sub.3, Cl or Br; and PA1 R.sub.6 and R.sub.8 are as previously defined.
X is H, Cl, Br, CH.sub.3, C.sub.2 H.sub.5, C.sub.1 -C.sub.3 alkoxy, CF.sub.3, SCH.sub.3 or CH.sub.2 OCH.sub.3 ; PA2 Z is CH.sub.3 or OCH.sub.3 ; and PA2 Q is sulfur or oxygen.
Levitt U.S. Pat. No. 4,127,405 discloses herbicidal thiophene and furan sulfonylureas such as, ##STR2## wherein R.sub.8, R.sub.9, R.sub.10, Q, X and Z are defined as above.
U.S. Ser. No. 153,279 discloses herbicidal thiophene sulfonylureas such as, ##STR3## and R is C.sub.1 -C.sub.4 alkyl, NO.sub.2, Cl, Br or SO.sub.2 NR.sub.1 R.sub.2 ; and
U.S. Ser. No. 196,167 discloses herbicidal thiophene sulfonylureas such as, ##STR4## wherein A.sup.1 is H, Cl, Br, C.sub.1 -C.sub.4 alkyl, OCH.sub.3, NO.sub.2 or CF.sub.3 ;
J. Drug. Res. 6, 123 (1974) discloses antidiabetic thiophene sulfonylthioureas such as, ##STR8## where R is pyridyl.
The presence of undesired vegetation causes substantial damage to useful crops, especially agricultural products that satisfy man's basic food needs, such as soybeans, barley, wheat, and the like. The current population explosion and concomitant world food shortage demand improvements in the efficiency of producing these crops. Prevention or minimizing the loss of a portion of valuable crops by killing, or inhibiting the growth of undesired vegetation is one way of improving this efficiency.
A wide variety of materials useful for killing, or inhibiting (controlling) the growth of undesired vegetation is available; such materials are commonly referred to as herbicides. The need exists, however, for still more effective herbicides that destroy or retard weeds without causing significant damage to useful crops.